With increasing extreme obesity and an aging population, the electric bed has become a popular piece of furniture. Nonetheless, most electric beds have a problem at present, namely a head bed, bed frame, or a bracket is away from a bed-rest at a certain distance when the head board raises, in which case, it is possible that some articles such as a pillow, and etc. would fall into the bed frame through the gap with the bed-rest. Additionally, when the head board rises, the position of the head changes relative to a bedside table, head and back is too far from the bed-rest, so it is possible to feel non-dependent. The aforementioned would impact on the conveniences and comfort of a user.
At present most electric beds use two methods to solve the above problems. The height of soft roll for the bed board is increased and elastic filling is extended toward the bed board to compensate for the distance from the bed-rest when the bed board rises at maximum angle. This method improves the above problems to some extent, but the distance from the bed-rest is not eliminated, many elastic materials are used, and appearance and shape are greatly limited.
The electric bed uses separate upper and lower bed frames. The upper bed frame is arranged in a lower bed frame guide rail by a bearing. The upper bed board and the lower bed board are attached with two flexible woven belts. When the head board is raised, the upper bed frame is pulled up by the woven belts to move toward the bed-rest, so that the head board keeps a certain distance from the bed-rest. It should be mentioned that this woven belt method was a break through. Nonetheless, this method had many defects and limitations. First, the structure and stress features limited use of the head board during beginning a raising stage. In order to solve this problem, most electric beds have a sectioned structure. The woven belts are loosened so that they pull the upper bed frame till the head board is raised at 20-30°. Thus the distance is not controlled during the beginning raising stage of the head board, and the woven belts are loose, causing uncontrolled risks such as twisting and knotting. Secondly, as the flexible woven belts bear tensile force only, it is impossible to solve the problem that the upper bed frame slides by force toward the bed-rest.